Polishing-machine.



'w. LA HODNYQ POLISHINGMACHINE. APPLICATION FILED JUNE 18', I912.

2 SHEETS-SHEET 2.

Patented June 8,1915.

UNITED strA'rEs I POLISHING-MACHINE.

This invention relates more particularly to improvements in machines used for polishing plane glass surfaces, such as thefiat surfaces of mirrors and plate glass.

' The rotary polishing heads most commonly employed in these machines consist of a circular disk connected by a flexible or universal joint to a rotary shaft andv provided with a felt polishing pad which bears and rotates on the surface to be polished. In the use of these polishing heads a considerable proportion of the polishing material, usually consisting of rouge and water, is thrown or swept aside by the rotarymotion of the head and is not drawn in under the polishing pad as it should be, so that the polishing operation is materially impeded. The pads on these heads wear away much faster at their outeredges than at their centers, owing to the greater travel and consequent wear of the edges and it is, therefore,

- necessary to frequently dress or true up'the perfectly, will draw' the rouge in under it,

- will cause the polishing. pad to wear evenly.

pads to remove the high central portions. Furthermore, when the bottom faces of the padsare not flat, the rouge becomes dry and cakes on the pads in places and scratches the glass. Another serious objection to these heads is that, since they are driven continu-. ously in the same direction, there is no chance for the caked rouge or particles of grit-,' which become embedded in the surface of the pad, to free themselves and allow the pad to polish out the scratches thus made.

The object of this invention is, to avoid these objections and provide an efficient polishing .devicewhich will polish rapidlyv and throughout the extent of its surface and always remain flatynotwithstanding irregularities in the surface of the work, will prevent tl e drying and caking of the rouge on the pad and will operate to free itself of gritty particles in such a; way a to avoid scratching the surface of the wor This is accomplished by constructing thepolishing device with a rotary tarrier or. body onwhich polishingheads are mounted, so that they revolve with the carrierz and are also free to PATENT OFFICE...

WILLIAM LA HODNY, or BUFFALO, NEW YORK.

Specification of Letters Patent.

Patented June 8, 1915.

Application fil ed June s, 19 m. Serial No. 704,359.

'be rotated by frictional contact with the surface of the work about axes eccentric to the -axis of the carrier, and to assume positions at an angle to the plane of rotation of the carrier, so as to bear flat upon the surface being polished when the surface is not level,

' polishing machine embodying the invention.

Fig. 2 is a sectional planthereof in line 22,

- Fig. 1. Fig. 3 is a sectional elevation on an polishing device of modienlarged scale of a fied construction.

Like reference characters refer to like parts in the several figures.

With the exception of the construction and arrangement of the polishing devices, the machine illustrated in the drawings is of ordinary construction.

A represents the bed or table on which the plate of glass B, or other plane surfaced article to be polished, is placed, and C represents rotary shafts, above the table, on the lower ends of which the polishing devices D are mounted. The bed or table is arranged to reciprocate the work beneath thepol'ishing devices, and the shafts C are adapted to x be moved vertically in their bearings by a Y lever c for lowering and raising the polish- ,ing devices into and out of contact with the -ishing devices D, but any desired number,

one or more, of the polishingdevices can be used in each machine.

Each polishing device comprises a rotary body or carrier E which is connected to the lowerv end of the shaft 0, so as to rotate therewith, and polishing heads F which are rotatably mounted on the carrier to rotate about axes eccentric to the shaft C, or axis of rotation of the carrier. The carrier is connected to the shaft C by-a flexible or ball and socket joint 6, such, for example, as used for the ordinary polishing heads, which causes the carrier to rotate with the shaft,

.but at the same time permits the. carrier to tilt or rock on the shaft sufficiently to equali'zethe pressure of the polishing deviceson I a surface which is uneven or not level. Ti The and the carrier may be of any suitable construction adapted to support the polishing heads, so that they can rotate about axes eccentric to the axis of rotation of the carrier.

Each polishing head can be journaled on the carrier in any suitable way which will permit it to rotate freely about its own axisss on the carrier and also tilt or rock relative to the carrier and to the other polishing heads sufliciently to enable the several-heads to bear fiat on the diflerent portions of the work engaged thereby, when the surface of V Different ways of journaling the heads on the work is not perfectly level or plane.

the carrier are shown in the drawings. In the simplest construction, illustrated in Figs. land 2, each head consists of a single circular disk provided on its underside with a polishing pad 7 of suitable material, such as felt, and having a central upright stud f with a spherical upper end which is confined in a correspondingly shaped socket f on the carrier, in which it is adapted to rotate freely. and also to rock slightly.

In the construction shown in Fig; 3, the

i polishing head comprises upper and lower disks F and F The lower disk is provided on its under side with the polishing pad f and is connected to the upper disk by a cen tral ball and socket joint, or other suitable loose connection g, and by pins 9 on the lower disk near its periphery which extend loosely through holes g in the upper disk and are surrounded between the disks by springs 9 These connections cause the lower disk to turn with the upper disk, but

"permit it to rock or tilt relative thereto.

The upper disk is journaled on the carrier by. a central stud shaft h, ail anti-friction thrust bearing h of any suitable construetion being provided between the upper disk and its carrier to insure the free rotation of the polishing head on the carrier. When two or more of the polishing devices D are employed, as in the machine illustrated, the shafts C are preferably driven in opposite directions, as by intermeshing gear wheels 5, and the polishing devices are so arranged that the polishing heads F on one carrier E will intermesh with .or enter the spaces between the polishing heads F on the adjacent carrier, so that the polishing heads of the adjacent devices travel in opposite directionsin overlapping circular paths.

By journaling the polishing heads eccentrically on the rotary carrier, as explained, the heads will travel bodily in circular paths concentric with theaxis of the cor and will alsobe revolved about their ownaxes, in an opposite direction by frictional contact with the work. The travel and wear of all parts of the polishing pad on each head will, therefore, be substantially equalized and the working face of the pad will always remain flat, instead of wearing more rapidly at the circumference and becoming convexed, as in the case of the ordinary polishing head. Even should-the working face of the pad wear so as to have an inclination relative to the plane of rotation of the head, on account of the work'table or surface of the work not being perpendicular to the carrier shafts, nevertheless the face of the pad will remain flat or plane and operate perfectl The necessity for dressing or truing up t. e surfaces of the pads is thus practically eliminated.

I Since the heads travel bodily about the axis of the carrier, they act to draw a considerable proportion of the polishing ma. terial inwardly, or toward the center of the carrier, and to counteract the tendency to throw it outwardly by centrifugal aetion, thereby effecting a more equal distribution of the material under the polishing pad andutilizing the whole surface of the pad for polishing. This greatly increases the rapidity of the polishing operation, and" the rougewill not become dry in spots and cake on the pad. If partlcles of rit, which will scratch the work, become em edded in the pad, the:

change of positions of the pad relativetojts path of travel about the axis of the carrier, due to the rotation of the polishing headon its own axis, will cause the grit to be dis lodged and give the polishing head an opportunity to polish out any scratches made a by the grit. The connection of the polishing heads to the carrier by joints which allow the heads to tilt relative to the carrier enables the heads to assume the different positions necessary to operate properly on surfaces which are not even or level.

While the device above described is primarily intended for polishing glass, it is nevertheless also adapted for polishing other .materials and a devlce of similar construction is also adapted, when supplied with suitable abrasive material, forgrinding flat surfaces.

I claim as my invention:

1. In a device of the character described, the combination of a support for the work, a positively driven rotary carrier which is mounted to tilt relative, to said work sllpport, and polishing heads mounted on said carrier to rotate freely thereon about axes eccentric to the axis of rotation of said carrier and to tilt relative to said carrier.

2. In a device of the character described, the combination of a positively driven rotary member, a carrier connected to said member by a joint which causes the carrier carrier to tilt relative to the work, and polishing heads which are rotatably mounted eccentrically on said carrier and are free to x be rotated thereon by frictional contact with the work.

' 3. In a device of the character described, the combination of a, positively driven rotarycarrier, a polishing head mounted on said carrier and comprising an upper disk journaled to rotate freely on said carrier .about an axis eccentric to the axis 'of rotathe combination of oppositely rotating posi-' tively driven carriers, and heads mounted on each of said carriers so as to rotate freely about axes eccentric to the axis ofthe carrier and tilt relative thereto, said carriers being arranged so that in the rotation there'- of the heads on one carrier enter the spaces between the heads on the ad acent carrier.

5. In a device of the character described, the combination of a work support, oppo-s I sitely rotating positively driven carriers, heads which are rotatably mounted on each of said carriers and are free to be rotated thereon about axes eccentric to the axis of the carrier by rfrictional contact with the work, said heads being also free to tilt relative to the work support, and'said carriers being arranged so that in the rotation thereof the heads on one carrier enter the spaces between the heads on the adjacent carrier, substantially as set forth.

Witnessmy hand this 13th day of June, 1912.

- WILLIAM LA HODNY.

Witnesses N. KERKER, Enrrn L. STULT. 

